Add OEMCrypto_GetKeyHandle fuzzer

Merged from https://widevine-internal-review.googlesource.com/174934

Change-Id: If44423ed51cc2ff10c1b471d39db962a653d8c14

libwvdrmengine/oemcrypto/test/fuzz_tests/oemcrypto_get_key_handle_fuzz.cc

@@ -0,0 +1,47 @@
+// Copyright 2023 Google LLC. All Rights Reserved. This file and proprietary
+// source code may only be used and distributed under the Widevine
+// License Agreement.
+
+#include <vector>
+
+#include "FuzzedDataProvider.h"
+#include "OEMCryptoCENC.h"
+#include "oemcrypto_fuzz_helper.h"
+
+namespace {
+
+// Avoid calling non-trivial destructor.
+wvoec::OEMCryptoLicenseAPIFuzz& license_api_fuzz =
+    *new wvoec::OEMCryptoLicenseAPIFuzz;
+
+}  // namespace
+
+extern "C" int LLVMFuzzerInitialize(int* argc, char*** argv) {
+  wvoec::RedirectStdoutToFile();
+  license_api_fuzz.Initialize();
+  license_api_fuzz.LoadLicense();
+  return 0;
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  FuzzedDataProvider fuzzed_data(data, size);
+
+  const OEMCryptoCipherMode cipher_mode =
+      wvoec::ConvertDataToValidEnum(fuzzed_data, OEMCrypto_CipherMode_MaxValue);
+
+  // key_handle and key_handle_length parameters
+  size_t key_handle_length_data = fuzzed_data.ConsumeIntegralInRange<size_t>(
+      0, wvoec::MAX_FUZZ_OUTPUT_LENGTH);
+  std::vector<uint8_t> key_handle(key_handle_length_data);
+  size_t* const key_handle_length =
+      fuzzed_data.ConsumeBool() ? &key_handle_length_data : nullptr;
+
+  const std::vector<uint8_t> content_key_id =
+      fuzzed_data.ConsumeRemainingBytes<uint8_t>();
+
+  OEMCrypto_GetKeyHandle(license_api_fuzz.session().session_id(),
+                         content_key_id.data(), content_key_id.size(),
+                         cipher_mode, key_handle.data(), key_handle_length);
+
+  return 0;
+}